livepatch: Use lists to manage patches, objects and functions

Currently klp_patch contains a pointer to a statically allocated array of
struct klp_object and struct klp_objects contains a pointer to a statically
allocated array of klp_func. In order to allow for the dynamic allocation
of objects and functions, link klp_patch, klp_object, and klp_func together
via linked lists. This allows us to more easily allocate new objects and
functions, while having the iterator be a simple linked list walk.

The static structures are added to the lists early. It allows to add
the dynamically allocated objects before klp_init_object() and
klp_init_func() calls. Therefore it reduces the further changes
to the code.

This patch does not change the existing behavior.

Signed-off-by: Jason Baron <jbaron@akamai.com>
[pmladek@suse.com: Initialize lists before init calls]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 7 insertions, 2 deletions

diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index bd41b03a72d5..37d0d3645fa6 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -659,20 +659,25 @@ static int klp_init_patch_early(struct klp_patch *patch)
                 return -EINVAL;
 
         INIT_LIST_HEAD(&patch->list);
+        INIT_LIST_HEAD(&patch->obj_list);
         patch->kobj_added = false;
         patch->enabled = false;
         patch->forced = false;
         INIT_WORK(&patch->free_work, klp_free_patch_work_fn);
         init_completion(&patch->finish);
 
-        klp_for_each_object(patch, obj) {
+        klp_for_each_object_static(patch, obj) {
                 if (!obj->funcs)
                         return -EINVAL;
 
+                INIT_LIST_HEAD(&obj->func_list);
                 obj->kobj_added = false;
+                list_add_tail(&obj->node, &patch->obj_list);
 
-                klp_for_each_func(obj, func)
+                klp_for_each_func_static(obj, func) {
                         func->kobj_added = false;
+                        list_add_tail(&func->node, &obj->func_list);
+                }
         }
 
         if (!try_module_get(patch->mod))